What is hyperhidrosis (excessive sweating)?
Sweating is necessary to control the body temperature during exercise and when the body is hot. Sweating is regulated by the sympathetic nervous system and in about 1.0% of the population this system is revved-up and results in excessive sweating.
Excessive sweating is a condition known as hyperhidrosis and can occur in many areas of the body but is most common on the palms, feet and axillae (underarms).
How does hyperhidrosis affect people?
Regardless of where it is located, hyperhidrosis causes considerable social, psychological and occupational problems leading to a negative effect on the sufferer’s quality of life.
Shaking hands is embarrassing and working with paper and metals causes obvious problems making business and day to day life a struggle for those affected. Patients report that recreational sport can be difficult and some are even embarrassed to hold the hands of those they love.
Hyperhidrosis of the feet is often associated with an unpleasant odour, maceration of the toes and mycotic infections.
What causes hyperhidrosis?
Doctors don’t know exactly what causes hyperhidrosis although they have successfully linked it to over activity in the sympathetic nervous system, specifically the thoracic sympathetic ganglion chain which runs along the vertebra of the spine inside the chest cavity.
This nerve chain controls the glands, known as the apocrine and eccrine glands, responsible for perspiration throughout the entire body.
Sometimes people will sweat excessively because of other conditions such as hyperthyroidism, the menopause, obesity and sometimes psychiatric disorders. These causes must first be ruled out before primary hyperhidrosis can be diagnosed. Some medications can also cause excessive sweating. If the hyperhidrosis is generalised, it is necessary for the doctor to perform routine blood tests to ensure that there is no other cause.
At what age does hyperhidrosis start?
The typical age of onset of hyperhidrosis is in the teenage years; however it is not uncommon in children, especially in the hands and feet.
How can hyperhidrosis be treated?
There are a number of ways of treating hyperhidrosis which include the use of strong topical antiperspirants, tap water iontophoresis, Botox injections, oral medication and in some cases surgery where the thoracic sympathetic ganglion is cut. The effectiveness of these treatments varies with each person and the least invasive methods should be tried first. Surgery should be reserved as a last resort because there can be some very unpleasant side effects.
Aluminium chloride based antiperspirants are usually tried as a first option. There can be a difference in the level of performance and irritation caused by the different brands. More information on different antiperspirants can be found on the Hyperhidrosis Patient and Medical Staff Support Group UK web site.
If antiperspirants don’t work or only partially work the next treatment to try is tap water iontophoresis. The treatment uses electrical stimulation and is a safe, non invasive and effective way of treating hyperhidrosis of the hands, feet and underarms.
If tap water iontophoresis is not effective then the other treatments can be considered with advice from your doctor. More information on these treatment options can be found on patient support group web sites, see the links section for more details.
What is iontophoresis and how does it work?
Tap water iontophoresis involves applying a low intensity electrical current to the hands and/or feet or axillae by means of an iontophoresis machine and water baths containing ordinary tap water. Exactly how tap water iontophoresis works remains unclear; however the treatment has been shown to be effective in up to 98.5% of people making it a safe first line treatment option 1.
How effective is iontophoresis?
In a study using an i2ma machine 68 pairs of hands and feet (in 45 hyperhidrosis patients) were treated using ordinary tap water. Marked improvement was noted after six sessions and complete dryness was achieved after an average of 11 sessions (± 3) in all but one pair of feet giving a 98.5% success rate (the pair of feet had improved but didn’t satisfy the criteria for complete dryness).1 Please note the success rate can depend on the mineral content of the water used.
Most people with hyperhidrosis will experience complete cessation of sweating after the initial phase of treatment; this sweat free period can last from a few days to a month or so, depending on the individual. After the initial intensive treatment phase the hyperhidrosis can be kept under control by regular maintenance treatments. The frequency of maintenance treatments varies from person to person and may be twice weekly or even monthly.
1. Elkhyat A and Agache P. Treatment of hyperhidrosis by iontophoresis of weakly mineralised water. 1993. Cutaneous Biophysics Laboratory, Department of Functional Dermatology, 25030 Besancon, France. (Available on request)
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